I've been reading the input of this RF Receiver by connecting it's DATA pin to an Analog Pin from my Arduino and sending it to the Serial Monitor. If I don't transmit absolutely anything, it reads some noisy input. I already checked that the Analog Pin doesn't introduce any noise by placing a 10K resistor between it and ground. BUT when I do transmit, let's say, a constant ON-OFF pulse train with a delay of 100ms, It reads just as if there was no noise. If I look closely at the Serial Monitor I could notice that none of the zeros got disturbed at all, it's just plain zeroes and 700 (approx). So my conclusion is that the RF Receiver goes crazy if it doesn't detect anything. I've read that you are supposed to transmit some pulse train ALL the time, even if you don't want to transmit anything in particular in order to keep the Receiver at peace, and for it to not mess with your important data. My question is, is there any way to bypass this? The RF Transmitter side is going to be powered by battery, and I suppose that this constant pulse train would drain it pretty quickly. Thank you in advance.
That is normal, the receiver outputs noise.
Those very cheap RF transmitters and receivers have no chip on the RF board that takes care of the protocol (how the radio signal is modulated and how the data is translated to RF data). The Arduino has to do everything, the timing, the protocol, the detection of data, everything.
The transmitter can be turned on and off. That's why it is called ASK modulation (on and off).
The receiver has an automatic gain and receives everything. When nothing is transmitted the receiver increases the gain until it receives a lot of noise. When a digital input is used with an interrupt it could be thousand(s) interrupts per second of useless noise.
To make those work, you need a library that does the transmitting and receiving, including a protocol for the transmitted data. The best library is the VirtualWire/RadioHead. I suggest to use the RadioHead in RH_ASK mode. There are "ask" examples that show how to use the library.
The VirtualWire/RadioHead is really good in detecting a packet of data between the noise.
If you don't want to sacrifice your Arduino for the RF protocol, then you can buy transceiver modules. They have a chip on the RF board that takes care of transmitting and receiving.
